Shimano launches 12-speed GRX Di2 groupset

Shimano is expanding its Gravel range by introducing the new GRX Di2 2 x 12 speed groupset, for optimized transmission options.

The family of 12-speed gravel components is electrified with the arrival of the new GRX RX825 Di2 2 x 12-speed groupset. These components combine proven, high-performance electronic shifting with transmission options optimized for adventure-seeking, fun-seeking cyclists, and even couriers. This new groupset offers comfortable shifters for more control, a SHIMANO SHADOW RD+ rear derailleur for improved chain retention and a front derailleur designed for precise shifting. The group’s introductory price is €2,329.

A Di2 transmission

  • A group now electronic with quick and precise gear changes, and a wireless cockpit for ultimate performance and absolute reliability.
  • An optimized gravel transmission – The arrival of 12 speeds for unrivaled efficiency and Shimano HYPERGLIDE+ technology for smooth shifting, whatever the conditions.
  • Improved ergonomics – The perfect balance between comfort and grip. This new generation offers unrivaled ergonomics, a cleaner cockpit and even more customization.

GRX 2 x 12 transmission options

This new generation of electronic components is an additional transmission option in front of the mechanical version unveiled last year. The new GRX RX825 Di2 levers, complementary satellite buttons, derailleurs combined with existing components (cassette, crankset, chain) offer a high-performance and reliable 12-speed transmission in electronic version to all gravel riders.

As with the RX820 mechanicals, riders have the choice of a 48-31 tooth double crankset or a 46-30 tooth version with the RX620 crankset. Likewise, riders can choose between an 11-36 or 11-34 tooth cassette for a wide choice of ratios with close ratios. All offering an always optimal pedaling cadence.

GRX RX825 Di2 compatible gear options:

  • 48/31 teeth, RX820 crankset
  • 46/30 teeth, RX610 crankset
  • 11-36 teeth, HG710 cassette
  • 11-34 teeth, R9200, R8100, R7100 cassettes

Shimano Di2 electronic shifting for Gravel

Like its similar 12-speed groupsets, DURA-ACE, ULTEGRA, and SHIMANO 105 Di2, the new GRX Di2 is wired, with a central battery that provides stable, long-lasting power to the front and rear derailleurs. Smaller diameter wires run from the battery to each derailleur, eliminating junctions and streamlining the assembly process.

Shimano Di2 wireless cockpit

The Shimano 12-speed GRX Di2 groupset allows for a wireless cockpit where the raised hoods have a non-slip coating for better grip and more confidence in your riding. We also find, as on the GRX RX815 Di2 DUAL CONTROL controllers, a third button for even more intuitive gear changing and always with optimal control of the mount on bumpy terrain. This third button can be configured to scroll through information on your GPS and thus increase your experience of the Shimano Di2 electronic transmission.

New special Gravel ergonomics

The new DUAL CONTROL levers benefit from a more curved shape to adapt to handlebars with Flare. The integration of the cables is well thought out to provide a clean cockpit. The change in hand position, from the hanger to the handlebars, is fluid. Cyclists will feel less pressure on their hands with this new ergonomics.

ST-RX825 – DUAL CONTROL hydraulic levers

  • Di2 wireless connectivity
  • 2 x 12-speed Dual-Control
  • Levers with ergonomics optimized for Gravel practice
  • New special curved handlebar shape with Flare
  • Anti-slip coating
  • Customization of up to 3 Di2 buttons via the E-TUBE PROJECT Cyclist application
  • Powered by replaceable flat batteries (2 x CR1632) with an estimated lifespan of 3 and a half to 4 years
  • Weight : 415 gr / pair
  • PPC: €494.99 for the hydraulic brake-caliper assembly

Customizing Di2 controls with your accessories

The new Di2 system also allows the setting of Di2 buttons to operate various accessories, another key benefit of electronic shifting. By pressing one of the satellite buttons on Shimano shifters, whether on the top of the cover, in the pocket of the handlebars or from a button integrated into an aero handlebar for example, cyclists can maintain their effort more consistently , without needing to move your hands. Like the 3rd button on the GRX Di2 dual-control controllers, these satellite buttons can be assigned various functions such as changing gears, controlling lights and compatible GPS, or as an RPM trigger button during training.

The SHIMANO SHADOW RD+ rear derailleur

The RX825 rear derailleur features pioneering SHIMANO SHADOW RD+ technology. With its on/off lever, SHADOW RD+ technology makes it easier to remove the rear wheel when it is deactivated. When activated, the transmission is put under additional tension for smoother, quieter shifting.

As with Shimano Road 12-speed Di2 drivetrains, the rear derailleur is the brain of the drivetrain. It communicates wirelessly with controllers, compatible GPS devices and the E-TUBE PROJECT Cyclist app via a smartphone. It also houses the charging port and a multifunction button that allows riders to easily check the battery level, pair via Bluetooth, and enter adjustment mode for both derailleurs.

RD-RX825 – Rear derailleur:

  • SHIMANO SHADOW RD+ technology for better chain retention
  • Built-in D-FLY connectivity and charging port
  • 12 speeds
  • Compatible with 11-34 and 11-36 tooth cassettes
  • Weight : 310g
  • PPC : €389.99

Optimized chain line for more clearance

Like the very first GRX groupsets, the RX825 range uses a wider chainline, +2.5mm, to provide more clearance. This is especially useful with the trend for wider tires and sometimes muddy playgrounds.

FD-RX825 – Front derailleur

  • +2.5mm chain line compared to Road front derailleurs
  • More clearance for large section tires
  • 2 x 12 speeds
  • Weight : 142g
  • PPC : €219.99


Using the Shimano E-TUBE PROJECT Cyclist app, riders can choose between different shift intervals, customize shift button assignment (which buttons perform which functions), program different shift modes like Synchronized and Semi-Synchronized modes. The launch of the RX825 also coincides with the launch of the new FRONT SHIFT NEXT feature.

With this firmware update you can use the E-TUBE PROJECT Cyclist app to program any Di2 12-speed button to move the front derailleur to the chainring you are not currently using and then shift again with the same button. This new feature is not only compatible with the GRX RX825 groupset, but also with the Shimano Route 12-speed Di2 family of components. The result is easier, more intuitive shifting for beginner riders and faster decision-making for experienced riders in the heat of competition.



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